Air conditioning apparatus



June 9, 1936. G. H. SIMMONS 2,043,450

AIR CONDITIONING APPARATUS Filed June 26, 1955 2 Sheets-Sheet looooooooaooooooooeoooo 2. 0000000000000000 o a Z v Z J o m o o o o o o om o q o o w o e 0 o o o o z J J z i June 9, 1936. H, MMON 2,043,450

AIR CONDITIONING APPARATUS Filed June 26, 1955 2 Sheets-Sheet 2 H0 7 WAT51? I J67 Gordamf/ Patented June .9, 1936 PATENT QFFICE AIRCONDITIONING APPARATUS Gordon H. Simmons, Milwaukee, Wis., assignor toWilliam M. Devine, Chicago, Ill.

Application June 26, 1935, Serial No. 28,434

8 Claims. (01. 257-3) My invention relates generally to air conditioningapparatus, and more particularly to a unit type air cooling apparatuswhich will be efiicient in operation and adapted for use in stores, of-

fices, and homes.

It is an object of my invention to provide an improved conditioningapparatus having an improved heat transfer unit and an improvedarrangement for dehumidifying the air.

Other objects will appear from the following description, referencebeing had to the accompanying drawings, in which Fig. 1 is a frontelevation of the unit, portions thereof being shown as broken away toillustrate lo the interior construction;

Fig. 2 is a central, vertical, sectional view taken on the line 2--2 ofFig.1;

. r Fig. 3 is a horizontal sectional view taken on the line 3-3 of Fig.1;

Fig. 4 is a horizontal sectional view of a modified form of myinvention, in which the unit may be optionally used for heating orcooling;

Fig. 5 is a diagrammatic view of the combined heating and cooling unitshown in Fig. 4, and. illustrating the piping connections; and

Fig. 6 is a fragmentary sectional view taken on the line 6-6 of Fig. 4.

As shown in Figs. 1, 2, and 3, the air conditioning unit of my inventioncomprises generally, a casing In which is preferably of 'welded sheetmetal, and is preferably lined with a suitable insulating material toprevent condensation upon the external surface thereof.

Suitably mounted within the casing ID, are a plurality of headers l2,I4, l6, l8, and 20, the headers being attached to the casing by brackets22, 23, and 24. The brackets 24 may be formed integrally with a sheet 26which extends across the casing l0 and has a circular opening 28 there-0 in to receive the fan. A plurality of rows of copper tubes 3!] connectthe headers l2, l4, l6, l8, and 20 in series. As shown in Fig. 2, thereare preferably two staggered rows of tubes 30 connecting each of theheaders with the next header of the series. The copper tubes 30 areprovided with vertical heat transfer fins 32 and 34, the fins 22 beingentirely separate and unconnected with the fins 34. It will be notedthat the fins 32 are in thermally conductive relationship with only thetwo rows of copper tubes 30 which connect the headers l2 and I4. Thelower end of the header I2 is providedwith a suitable inlet fitting 36to which is connected the inlet pipe 38, while a similar fitting 40 isprovided at the upper end of the header 20 and has an outlet pipe 42connected thereto. The header I8 is provided with an air vent valve 44.

A drip pan 46 is located beneath the copper tubes -30 and is providedwith a drain connection 48 for a drain pipe 50.

The casing III has a rectangular shaped opening 52 inthe front thereof,portions of the casing wall being bent inwardly at 54 to form flangesfor the attachment of air deflecting louvers 56. These louvers arepivotally mounted on the flanges w 54 and may be individually adjustedto deflect the air in the desired direction.

A motor bracket 58 is suitably secured to the casing l0 and supports anelectric motor 60. This motor has a suitable fan or propeller 62 secured5 to its shaft. A suitable screen 64 may be provided to cover the rearopening 66 formed in the casing to prevent the entrance of foreignmatter.

It will be noted that the circulation of the water is in a generaldirection opposed to the flow 20 of air, and that the coolest waterflows through the tubes 30 which connect the headers l2 and 14. Thesetubes, and their thermally connected fins 32, will thus be cooler thanthe remaining tubes of the unit, and the greater proportion of condensa-25 tion will take place upon these tubes. It is desirable, and one ofthe features of my invention, that these tubes be thermally insulatedfrom the remaining tubes to as great an extent as possible, so that themaximum amount of condensation will 30 take place upon them and theirassociated fins. The arrangement of the fins in a vertical direction isalso of importance, since it makes it possible for the condensed watervapor to trickle downwardly along the fins and drop into the drain panB5 46. If the fins were arranged horizontally, the condensed water vaporwould tend to collect upon them and drip from one fin to another. Alarge number of drops of water would thus be carried with the air flowinto the room being cooled. &0 Since the air conditioning unit of myinvention is adapted to be used in stores and homes, and other furnishedplaces, this occasional spray of drops of water from the unit would behighly disadvantageous. I have found that with the fins extend- 415 ingvertically, all the condensed water vapor will adhere to the fins anddrain into the pan 46.

The unit of my invention is adapted to be connected to the regular watersupply if the temperature of the supply is sufficiently low. I havefound, however, that the unit is so efiicient that very beneficialefiects are obtained even though the difference between the temperatureof the water supply and the air is as little as 10 F. Thedehumidification of the air is, of course, in part responsible for theincreased comfort obtainable by the use of the air conditioning unit ofmy invention.

The water supply connection to the unit is preferably provided with asuitable 'valve by which the rate of flow to the unit may be easilycontrolled and the fan motor is preferably of a variable speed type andprovided with suitable manual or automatic controls for varying itsspeed in accordance with the atmospheric conditions. For example, athermostat may be utilized to control the fan motor to increase itsspeed when the atmospheric temperature exceeds a predetermined maximum,and at the same time the thermostat may control the valve which governsthe rate of fiow of the cold water to the unit so as to increase theflow when the predetermined maximum temperature is exceeded. It will benoted further, that the inlet to the header I2 is located at the bottomof the latter, whereas the outlet is located at the top of the header 20so that the warmest water is first discharged from the unit.

Under certain circumstances where the usual atmospheric temperatures areexceedingly high and'where a cooling water of a sufiiciently lowtemperature is not available, the cooling water may be recirculated bymeans of a pump, the

water circulating system including a suitable cooling device such as anice bunker or equivalent means.

. In Figs. 4, 5, and 6, I have shown a modified form of my invention, inwhich the apparatus is adapted for use as a heating unit or as a coolingunit. Means are also provided in the unit for humidifying the air aswell as dehumidifying it.

The unit comprises a casing I within which headers I2, I4, I6,- aremounted in a manner similar to the method previously described withreference to the apparatus shown in Figs. 1 to 3. Tubes I8 connect theheaders I2 and I6 and the header I6 with the header I4. As shown in Fig.6, these tubes arepreferably elliptical in transverse cross section, ormay be of any other suitable relatively flat shape, so that they willoffer the minimum resistance to flow of air past them. The tubes I8connecting the headers I2 and I6 are provided with vertical fins 80,while the tubes I8 connecting the headers "I6 and I4 are provided withconnecting fins 82. It will be understood that while only three headersand two sets of double rows of tubes are illustrated in Fig. 4, any

practical number of sets of tubes and connected headers may be utilized.I have found, however, that the arrangement illustrated in Fig. 4 isvery practical and efiicient.

The casing I0 extends rearwardly a sufllcient distance to enclose themotor 84. The open rear end of the casing I0 is provided with a screen86 which will prevent relatively large foreign particles from passingthrough the unit. In addition, a sheet of gauze 88, or other suitablerelatively fine filtering material, is suitably mounted across the rearopening so as to remove from the air small particles of dust and otherforeign matter which might otherwise settle upon the fins and tubes, andthereby decrease the rate of heat interchange. If desired, the sidewalls of the casing I0 which form the motor compartment, may have aplurality of screened apertures formed therein and an additional gauzefilter placed along the sides of the casing, thereby facilitating thefree entrance of air into the motor compartment.

As previously stated, the unit shown in Figs.

4, 5, and 6 is adapted for use as a heating as well as a cooling unit,and I have therefore diagrammatically illustrated in Fig. 5 appropriateconnections whereby the unit may be converted from one purpose to theother. In this figure, the pipe 90 which leads into the lower end of theheader I4 is connected to a two-way valve 92. The valve is soconstructed that it may alternately connect the pipe 90 with a pipe 94which is connected to a supply of cold water or may be connected with apipe 96 which forms a return to the boiler when the apparatus is usedfor heating by steam or hot water.

-A pipe 98 is connected to the upper end of header I2 and as shown inFig. 5 is connected to a two-way valve I00. The two-way valve I00 is soconstructed that it may alternatively connect the pipe 98 with a pipeI02 leading to a supply of steam or hot water or may be connected with apipe I04 leading to a water drain. A handle I06 is provided foractuating the valves 92 and I00, the handle having an extension I08which is connected by a link I I0 to an arm H2 secured to the plug ofthe valve I00. It will be understood that the illustration of the valvemechanism in Fig. 5 is diagrammatic in that in actual practice the plugsfor the valves 92 and I00 may be made integral.

When the apparatus is being used as a heater it may under manycircumstances be desirable to provide means for humidifying the air asan incident to heating it. To accomplish this purpose I provide a bellmouth spraying cup H4 attached to the central hub of the fan I I6. Wateris permitted to drop upon the interior or the rotating cup II4 from asupply pipeIIB which is connected to a convenient water supply main. Ahumidostat I20 is provided to control the flow of water through the pipeI I8 by means of a valve I22. If desired a manually operated valve maybe substituted for the valve I22. The valve I22 is electro-magneticallyoperated, the supply of current thereto being controlled by thehumidostat I20. Particularly 'when the apparatus is being used as aheating unit the thermostat I24 may be provided to control the operationof the motor 84. This control may be by the usual start and stop methodor the thermostat may be so constructed that it will vary the speed ofthe motor in accordance with the temperature of the room in which theheater is being used.

It will be readily understood that when the apparatus shown in Figs.4-and 5 is to be used as a cooling unit, the valves 92 and I00 will bein the positions indicated, and the cold water will flow from its supplythrough the valve 92, pipe 90, header I4, tubes I8 to header "I6,through the tubes to the header 12, through pipe 98 to valve I00 andthence through pipe I04 to a suitable water drain. When it is desired touse the apparatus as a heater, the valves 92 and I00 will be shifted totheir opposite positions by the handle I06 and the steam or hot waterwill be supplied through the pipe I02, valve I00, pipe 98 to the upperend of header 12 through the tubes 18 to the header I6 and from theheader I6 to the tubes which connect 'it with the header I4, from theheader 14 through pipe 90 to valve 92 and from thence through the pipe96 through the steam condensate or hot water return to the boiler."

The operation of the humidifying apparatus will be readily apparent,since when the humidity drops below a predetermined percentage the valveI22 will be opened and water permitted to drop from the pipe H8 upon thespraying cup H4. The droplets of water will be carried by the flow ofair induced by the fan H6 and upon being heated by the tubes l8, thewater will evaporate to increase the humidity of the air. Any waterwhich is not evaporated will collect upon the fins 82 and will drop intothe drip pan 46. (In Figs. 4 and 5 the drip pan is not shown but it willbe understood that the construction of the unit shown in Figs. 4 and 5is generally similar to that shown in Figs. 1 to 3 inclusive.)

By the use of the generally oval shaped tube 18, the surface area of thetubes relative to the flow therethrough is increased and in addition theresistance to air flow past the tubes is decreased, thus improving theheat exchange char acteristics of the unit.

While I have described preferred embodiments of my invention it will beunderstood by those skilled in the art that numerous modifications andvariations thereof may be made without departing from the basicprinciples thereof.

Having thus described my invention, what I claim asnew and desire tosecure by Letters Patent of the United States is:

1. An air conditioning unit type apparatus of the class describedcomprising a casing, a plurality of vertically positioned headerstherein, two groups of spaced horizontal tubes connecting said headersin series, means for circulating a fluid through said headers and tubes,a pair of groups of vertical fins each group being thermally connectedwith a group of said tubes respectively, a drip pan located beneath saidfins, and a motor driven propeller fan for forcing air successively pastsaid groups of tubes and fins.

2. In an air conditioning apparatus of the class described, thecombination of a casing, a plurality of vertical headers located thereinat the sides thereof, a plurality of groups of spaced horizontallyextending heat conducting tubes connecting said headers in series, amotor driven fan for forcing air past said tubes, means for supplying acooling medium to the header connected to the tubes most remote fromsaid fan, a group of vertical fins thermally interconnecting the groupof tubes most remote from said fan, a second group of vertical finsthermally interconnecting the remaining groups of tubes, and a drip panlocated beneath said fins to receive condensed water which may drip'fromsaid fins.

3. In a unit type air conditioning apparatus, the combination of aplurality of vertical headers, tubes connecting said headers in seriesrelationship, means for circulating a temperature changing fluid throughsaid headers and tubes, a motor driven fan for forcing air past saidtubes, a spraying member secured to said fan, and means for supplyingwater to said spraying memher.

4. In an apparatus of the class described, the combination of aplurality of vertical headers, horizontal heat transfer tubes connectingsaid headers in series, means for circulating temperature changingmedium through said tubes, 9, motor driven fan for forcing air past saidtubes, 9. water spraying member secured to said fan, and means forsupplying water to said member, said 5 means including a humidostatcontrolled valve for regulating the quantity of water supplied to saidspraying member. Y

5. An air conditioning unit type apparatus of the class describedcomprising a plurality of vertically positioned headers, groups ofspaced horizontal tubes connecting said headers in series, means forcirculating a fluid through said headers and tubes, a plurality of setsof vertical fins, one set being thermally connected with one only ofsaid groups of tubes, a drip pan located beneath said fins, and a motordriven fan for forcing air successively past said groups of tubes andsets of fins.

6. In an air conditioning apparatus of the class 20 described, thecombination of a casing, a plurality of vertical headers located at thesides thereof, a plurality of groups of heat conducting tubes connectingsaid headers in series, a motor driven fan for forcing air successivelypast said groups 25 of tubes, means for supplying a cooling medium tothe header connected to the tubes most remote from said fan, a group ofvertical fins thermally interconnecting the group of tubes most remotefrom said fan, a second group of vertical fins thermally interconnectingthe remaining groups of tubes, and thermally insulated from said firstgroup of fins, a drip pan located beneath said fins to receive condensedwater which may drip from said fins, and a thermostat to control thespeed of said motor driven fan.

'7. In a unit type air conditioning apparatus, the combination of aplurality of vertical headers, tubes connecting said headers in seriesre- 40 lationship, valve means for circulating a temperature changingmedium through said headers and tubes, a motor driven fan for forcingair past said tubes, a spraying member secured to said fan, means forsupplying water to said spraying member, a humidostat controlled valvefor regulating the rate of fiow of water to said spraying member, and athermostat operatively connected to control the operation of said motordriven fan. 50

8. In an apparatus of the class described, the combination of aplurality of vertical headers, spaced horizontal heat transfer tubesconnecting said headers in series, said tubes being generally ellipticalin cross section and having their major transverse dimension in ahorizontal plane, means for circulating cooling water through saidtubes, a motor driven fan for forcing air past said tubes, a waterspraying member secured to the hub of said fan, and means for supplyingwater to said member, said means including a humidostat controlled valvefor regulating the quantity of water supplied to said spraying member.

- GORDON H. SIMMONS.

